John geehaedt



(No Model.)

J. GERHARDT.

COMPENSATION PENDULUM. No. 352,461. Patented Nov. 9, 1886.

7 WITNESSES: INVENTOR ATTORNEYS.

UNITED STATES PATENT OFFICEQM JOHN GER HARDT,

OE MONTREAL, QUEBEC, CANADA, ASSIGNOR TO HIMSELF AND SAMUEL DAVIS, OF SAME PLACE.

-COMPENSATlON-PENDULUM.

SPECIFICATION forming part of Letters Patent No. 352,461, dated November 9, 1856.

Application tiled June 5, 1886. Serial No. 204,218,

(No model) To aZZ whom it may concern:

Be it known that I, JOHN GERHARDT, of Montreal, in the Province of Quebec and Dominion of Canada, have invented a new and Improved Oompensating-Pendulum, of which the following is a full, clear, and exactdescription.

The object of my invention is to provide an accurate and reliable compensating-pendulum which shall be cheap, durable, and not liable to get out of order.

To this end my invention consists, principally, of a oonipensatingrod and pendulumrod, both made of the same metal, combined with pivoted connecting devices supported at one end by the compensating-rod, and from which the pendulum is suspended, so that the contraction of the compensating rod willlower the pendulum and its expansion will raise the pendulum in exactly the degree that the pendulum itself expands and contracts under the influence of the same temperature with the compensating-rod.

The invention also consists of means for adjusting the compensatingrod,whereby thesaid rod may be used as a regulator for the pendulum.

The invention also consists of the construction, arrangement, and combination of parts,

all as hereinafter described and claimed.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresponding parts in both the figures.

5 Figure 1 is a front elevation of my new and improved compensating-pendulum, and Fig. 2 is an edge'vicw of the same.

A represents the compensating-rod, which is made of the same metal as the pendulum B, or of a metal that expands and contracts under the influence of heat and cold in equal degree with the metal of the pendulum. The compensating-rod A is supported upon the projection C, so that any contraction or ex- Connected to the upper end of the compensatpansion of said rod will show at its upper end.

tion of the compensating-rod A,will raise and lower the pendulum B. The rod A should be of suitable length, and the levers D E should be so arranged that the movement of the free 5 5 end of the lever E will bejust equal to the expansion and contraction of the rod A, so that when the rod A and pendulum contract the lever E will be lowered to compensate for the contraction of the pendulum, and when the pendulum B and rod A expand the lever E will lift the pendulum an equal degree, and

thus accurately compensate for the effect that changes in temperature may have upon the pendulum. The pendulum is connected to the end of the lever E by thethin spring a, which is held between the opposite points b b, which constitute the point of oscillation of the pendulum, so the length of the pendulum is calculated from these points to itslower end. For regulating the length of the pendulum to increase or diminish its speed of oscillation, the ball ois not raised or lowered upon its rod as with a common pendulum, but the com pensating-rod A is raised or lowered by turn- 7 5 ing the nut d, which will communicate a like movement to the pendulum through the lovers D E. An index,f, and pointerg are combined with the rod A toassist in regulating the pendulum.

Constructed as described, the pendulum is not only accurately self-compensating, but is cheap, and not liable to get out of order, and serves also as the regulatingrod for the pendulum. S 5

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The combination, with the pendulum, of the supported compensating-rod and. the in- 0 termediate lever-connection, comprising a lever connected to the compensatingrod and a second lever connected with the aforesaid lever and with the pendulum, substantially as and for the purpose set forth. 9 5

2. The combination, with the pendulum B, of the compensating-rod A, supported upon the projection O, and connected to the pendulum by the connected levers D E, the pendulum-spring being held between the points b,

substantially as described.

3. The compensating-rod A, made longitudinally adjustable, in combination with the or support, of the nut working and supported 10 pendulum and the pivoted connected and conin said bracket or support and upon said rod, nccting levers D E, substantially as and for and the index, substantially as and for the the purposes described.

5 4. The combination,withthe c0111 ensating- T H lever A and adjusting-nut c of a l indexf JOEL GERIIARDD' Witnesses:

B. V. GRODJINSKI, O. SEDGWIOK.

purpose set forth.

and pointer g, substantially as described.

5. The combination,with the compensatingrod having a pointer and the apertured bracket l 

